Live reference channels for testing contribution links, decoders, players and CDNs. Each channel is a pre-encoded, verified loop (closed GOP every 2 s, exact Y′CbCr codes) played out without re-encoding; audio is encoded live from a sample-exact source. Pick the protocol your equipment speaks: SRT (MPEG-TS), RTMP or HLS. RTSP will follow once its AV sync is certified. The playout start time is published, so receivers can measure end-to-end latency from the frame number in the data strip.
Caller mode to port 8890/UDP with stream id read:<channel>. MPEG-TS with H.264 or HEVC and AAC. Add a latency suited to your path (e.g. 200–1000 ms).
Port 1935/TCP, H.264 channels only (HEVC would need Enhanced RTMP, not supported by most receivers).
fMP4 segments of 2 s aligned to the GOP, served over HTTPS. Works in browsers, set-top boxes and players.
Read the AV sync scale when you hear the blip, watch the frame ladder for drops, compare levels with the certificate. Automatic measurement: the WorldTV DVB-I analyser reads the data strip.